Laravel parse error: syntax error, unexpected T_CLASS, expecting T_STRING in artisan

i checked my php version

PHP 7.0.27 (cli) (built: Jan 23 2018 09:07:32) ( NTS )
Copyright (c) 1997-2017 The PHP Group
Zend Engine v3.0.0, Copyright (c) 1998-2017 Zend Technologies

But this is error appear when doing cron job

Parse error: syntax error, unexpected T_CLASS, expecting T_STRING or T_VARIABLE or '$' in /path_to_project/artisan on line 31
X-Powered-By: PHP/5.3.29 Content-type: text/html

and also test this code

<?php 
class Foo{}
echo Foo::class;

?>
output is :Foo

any help plz

via Chebli Mohamed